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31.
The effects of maternal employment and non-maternal infant care on development at two and four years
Differences in maternal employment during children's first year of life and children's entry into non-maternal care before the age of 1 year failed to predict differences in cognitive and socioemotional development at 2 and 4 years of age, after family background variables were controlled. Two samples were studied: a population sample of 1100 Bermudian children and a smaller subsample of children most of whom were determined to be at risk for developmental problems. To assess the effects of maternal employment, we compared infants with mothers who worked 20 or more hours a week to infants with mothers who worked less than 20 hours a week. To assess the effects of entry into non-maternal care before the age of one, we compared infants who were placed in regular non-maternal care before the age of one versus infants who did not experience regular non-maternal care before the age of one. The results revealed that family background variables frequently predicted many child outcome measures in both the total sample and the smaller research sample. After controlling for family characteristics, no differences were found between children whose mothers worked 20 or more hours a week when they were infants and children with mothers who worked less than 20 hours a week in either sample. In addition, age of entry into non. maternal care before the age of one did not significantly predict any child outcome measures. 相似文献
32.
We examined the effect of frequency ratios on the discrimination of patterns of alternating pure tones (ABABA). Listeners heard a repeating pattern presented in transposition (same frequency ratios between successive tones, different absolute frequencies) and were required to indicate when the pattern changed (different frequency ratios and absolute frequencies). Changes from patterns with simple frequency ratios to those with more complex ratios were more readily detected than were changes from complex ratios to simpler ratios. 相似文献
33.
To determine the relative impact of a number of family variables on children's performance of gender-typed household tasks, this study took account of the gender of the child, the gender of a sibling within the same age range (8–14 years), whether a first or second child and three parental variables: the degree of encouragement given to perform masculineand femininetasks, parental involvement in the same tasks, and parents' general egalitarianism. The sample consisted of 191 white, mainly Anglo Australian two-parent families, with the two oldest children in a boy—boy, girl—girl, boy—girl, or girl—boy sequence. To check on the robustness of effects, measures were taken on two occasions, on average 16 months apart. Among the family context variables, the gender of the child was the strongest contributing variable, with girls doing more feminine tasks than boys and boys doing more masculine tasks than girls. There was limited support for the proposition that first children do more housework than second children of the same gender, while the results for gender of sibling were small and inconsistent. Among the parental variables, encouragement had strong positive effects for feminine tasks (i.e., more encouragement by parents corresponded to more involvement by children). In contrast, parental involvement in the same tasks (modeling) and parental egalitarianism predicted only the performance of masculine tasks, and the direction of the effects was mostly negative (e.g., the more a father was involved in masculine tasks, the less a child did of those tasks). The results point to involvement in gender-typed activities being influenced by multiple factors, with parental encouragement and gender of child being most prominent among these. They also point to the value of sampling on more than one occasion and of considering separately the performance of feminine and masculine tasks.
This research was financially supported by the Australian Research Council. We are happy to acknowledge that support, together with the essential assistance of the Department of Education and the many parents and children who participated in the study. 相似文献
34.
Jennifer L. Fitzpatrick Elaine M. Hutton Riyana Babul Cheryl S. Cytrynbaum Joanne E. Sutherland Cheryl T. Shuman 《Journal of genetic counseling》1996,5(1):1-15
Congenital bilateral absence of the vas deferens (CBAVD) occurs in approximately 1.3% of infertile males and is thought to be, in most cases, a primarily genital form of cystic fibrosis (CF). Fourteen males with CBAVD considering microsurgical sperm aspiration from the epididymis (MESA) and in vitro fertilization were seen for genetic counseling and screening for CF. To retrospectively evaluate these patients' perceptions of the counseling and screening information, we conducted structured telephone interviews to assess their recall of information about CF and its impact on their health concerns and reproductive plans. We found that, as the health implications of CF are abstract and not as important to patients as the diagnosis of CBAVD itself, patients tend to view their CF status primarily in terms of their reproductive potential. Retrospective analysis afforded us an opportunity to identify the psychosocial issues of most concern to this unique patient population. 相似文献
35.
36.
Children chose between toys freely and with various restrictive contingencies. Sometimes play with a preferred toy was contingent on play with a nonpreferred toy. Sometimes play with a nonpreferred toy was contingent on play with a preferred toy. Another toy (free toy) was always available during contingency sessions. Because toy playing occupied the entire session the response system was closed. When one response increased in duration others had to decrease. An analysis of closed-system responding revealed that the restrictions of the closed system together with the restrictions imposed by the contingencies forced subjects to alter the proportion of time devoted to the three responses. A geometrical model representing the closed system and an analytical method based on distance are presented to describe the data. 相似文献
37.
This paper describes a computational method for weighted euclidean distance scaling which combines aspects of an analytic solution with an approach using loss functions. We justify this new method by giving a simplified treatment of the algebraic properties of a transformed version of the weighted distance model. The new algorithm is much faster than INDSCAL yet less arbitrary than other analytic procedures. The procedure, which we call SUMSCAL (subjectivemetricscaling), gives essentially the same solutions as INDSCAL for two moderate-size data sets tested.Comments by J. Douglas Carroll and J. B. Kruskal have been very helpful in preparing this paper. 相似文献
38.
A simple method for producing audio tapes with temporally synchronized messages is described. The duration and spacing of words can be precisely controlled. This method requires a minimum of elaborate equipment, yet synchronization is very accurate with highly intelligible speech. 相似文献
39.
Sandra Haber 《Sex roles》1980,6(1):129-138
The career aspirations of 50 female college seniors of lower- and middle-class backgrounds was assessed by a questionnaire and tape-recorded interview. Using a fourfold classification contrasting career choice with career commitment, the women were classified as innovative career oriented, innovative noncareer oriented, traditional career oriented, and traditional noncareer oriented. The career aspirations of these women, however, were not related to maternal employment patterns as previous studies have indicated. Rather, the perceived attitudes and direction of the parents was found to be a significant correlate of career choice and career commitment. It was concluded that maternal employment as a modeling variable may be unimportant for women of lower- and middle-class backgrounds.This article is based on a dissertation which was submitted in partial fulfillment of the requirements for the Ph.D. degree in the Graduate Center, City University of New York. The author expresses appreciation to Dr. Florence Denmark for her continuous support throughout the entire study and also thanks Dr. Bernard Seidenberg for his valuable suggestions on earlier drafts of this article. 相似文献
40.
Three experiments are described that studied the role of detailed graphemic analysis upon the ability to read text. College students named letters in various approximations to English, with frequency of individual letters constant. Findings were that later skill at reading varied with the order of approximation to English of the letters that were named, that the spacing of the letter sequences was important to this result, and, finally, that the influence of specific visual practice extended to the typeface on which the naming and reading were carried out. Hence, rather than a letter-by-letter process or its opposite, a wholly semantic analysis, reading is shown to be intimately dependent upon details of visual analysis of patterns or letter sequences. 相似文献